Why is it that metal 3D printing is almost exclusively used for prototyping? For right now, 3D printed engine components for aviation and aerospace applications are still the exception, rather than the rule. The short answer is that it has everything to do with qualification. The beauty of 3D printing is that every part can be made to be unique, but this comes with a major downside: it makes it very difficult to test parts systematically. Research teams from all over the world are already working on this issue, and they are about to be joined by a team from Phoenix Analysis and Design Technologies (PADT), who have been awarded an America Makes grant to develop a model that can efficiently test 3D printed lattice structures.

Phoenix Analysis and Design Technologies (PADT) is a provider of engineering products and services, including product development and 3D printing, and is based at the Arizona State University Research Park in Tempe. They are also the leader of Arizona Technology Council’s Additive Manufacturing Committee. The largest provider of numerical simulation in Southwest America, they are especially known for providing simulation services to heavy industry partners.

Those partners will also be involved in this newest research projects, as regular clients ASU, Honeywell Aerospace, and LAI International will be part of this effort to study 3D printed lattice structures. Also involved will be University of Pittsburgh professor and 3D printing guru Prof. Howard Kuhn. Specifically, they are aiming to build a ANSYS-based simulation model that can predict how these lattice structures perform in different circumstances and under different forms of pressure – which can drive product design for aerospace applications.

As US engineers will tell you, it is no easy feat to be awarded an America Makes grant, and PADT’s proposal was one of only seven selected (and one of only two led by a small business). America Makes itself will provide $138,000 for this this viability project, while PADT and its partners will put up $143,000 worth of in-kind labor. The project proposal was named ‘A Non-Empirical Predictive Model for Additively Manufactured Lattice Structures’.

As senior PADT technologist and proposal author Dhruv Bhate explained, their project is all about performance prediction. “While there are several efforts ongoing in developing design and optimization software for lattice structures in additive manufacturing, there has been little progress in developing a robust, validated material model that accurately describes how these structures behave,” he said. “We are honored to be chosen to research this important issue and provide the tools to enable entrepreneurs, manufacturers and makers to integrate lattice structures in their designs.”

Lattice structures are, of course, key in reducing the weight of 3D printed parts. While they bring a lot of design flexibility to the table and lower material costs and production times, aerospace and automotive engineers are still hesitant to use them. “The tricky part is not knowing how those structures will perform under different stresses,” Bhate said. “That is what our effort is trying to solve. We’re developing a material model, a mathematical representation, that makes predictions on how these structures are going to perform.”

However, America Makes was also especially attracted to the proposal’s suggestion to develop a first-of-its-kind online, collaborative living textbook on 3D printing. This should provide comprehensive, up-to-date and structured information, and should bring necessary data to engineers’ fingertips. This could provide a lot of clarity in a field that sees 50 papers being published every day, while PADT is also looking into educational programs that provide even more assistance.

During the project, PADT will develop validation methods for three different 3D printing processes, and will test plastic and metal laser 3D printers, as well as electron beam 3D printing hardware. The latter 3D printer will be provided by LAI International. Honeywell, who is no stranger to 3D printing itself, will provide access to the scanning equipment that is used to find defects. “We plan to show uniquely how our material model can be applied to any 3D printed process companies want to use,” Bhate said. “It’s not limited to any one type of material or 3-D printed process.”

If successful, this model could play a huge role in expanding the presence of 3D printing in industrial circles. Suraj Rawal from the Lockheed Martin Space Systems Company already highlighted the importance of this project. “We also recognize the significance of this work in lattice behavior modeling and prediction as an important contribution to help implement the design, manufacturing, and performance validation of structures in our innovative designs,” he argued.